Isolation of Triterpenoid Glycosides (Saikosaponins) from Bupleurum polyclonum Y. Li et S. L. Pan and Their Chemical Structures

Sixteen triterpenoid glycosides, named S13 to S25, S37, S38 and S40, were isolated from the root of Bupleurum polyclonum Y. Li et S. L. Pan, and their structures were determined from NMR spectral analyses. Among them, S24, S37 and S38 were found to be new substances, their structures being established as 30-β-d-glucopyranosyl 30-hydroxysaikosaponin-b₂, 2″-O-acetylsaikosaponin-b₂ and 3″-O>-acetylsaikosaponin-b₂, respectively.     

Ionophorous Properties of SY-1 (20-Deoxysalinomycin) in Rat Liver Mitochondri

SY-1 (20-deoxysalinomycin), a monocarboxylic polyether antibiotic closely related to salinomycin, caused a rapid release of previously accumulated alkali metal cations by valinomycin or monazomycin in rat liver mitochondria, and simultaneously reversed swelling of mitochondria.

With a strict specificity for substrate and cation, SY-1 exhibited a property of inhibiting mitochondrial functions such as substrate oxidation, oxidative phosphorylation and ATP hydrolysis induced by valinomycin or monazomycin, In comparative study with salinomycin, SY-1 was found to be more effective on the mitochondrial functions than salinomycin.

On the basis of the results so far obtained, the inhibitory effect of SY-1 on mitochondria is interpreted as a result of interaction with essential cations, especially with K⁺, in mitochondria.     

Isolation and Characterization of Plant Growth Substances in Immature Seeds and Etiolated Seedlings of Phaseolus vulgaris

From the immature seeds of Phaseolus vulgaris cv. Kentucky Wonder GA₁, GA₈, GA₃₈, ABA and GA₈ glucoside were isolated, and GA₄, GA₅, GA₆ and GA₃₇ were identified by GC or GC-MS. Unknown substance, AB–II, was also suggested to be present in the immature seeds. In the etiolated seedlings glucosyl esters of GA₁ and GA₃₈ were identified by GC. GA₈ glucoside and AB–II were shown to be present by the histograms.     

Solubilization and Characterization of Ovomucin without Chemical Modification

1. The egg white, thick and thin fractions, was solubilized in 1.0% SDS solution by vigorous mixing and subjected to gel filtration on a Sepharose 4B column, eluted with 1.0% SDS. The isolated thick and thin ovomucins were found by analytical disc electrophoresis to be free from contamination with lysozyme.

2. In the velocity sedimentation the two ovomucin fractions behave similarly, both comprising at least two components with sedimentation coefficients 35 S and 30 S.

3. The chemical compositions of the two ovomucin fractions showed only notable difference in that the carbohydrate content of the thick white ovomucin was somewhat higher than that of the thin white ovomucin. The amino acid profiles of the two fractions were similar.

     

A Screening Procedure on the Inhibitors of Substrate-incorporation in Tumor Cells Methodological Survey and Its Evaluation

A comparative study of inhibition on the substrate-incorporation in several species of tumor cells has been achieved in combination with the antibiotics having different action mechanisms. It was thus revealed that a large part of the antitumor antibiotics so far examined showed a marked inhibitory response even at a low concentration. Particularly, the antibiotics whose action mechanism were established primarily on cell membrane were markedly sensitive. An apparent difference in the sensitivity was observed in some groups of antitumor antibiotics which act on nucleic acid synthesis. A methodological survey together with an evaluation of this procedure is discussed.     

The Photochemical Reaction of Pentachlorophenol

The chemical structure of a yellow C₁₈-compound (IV), isolated from the decomposition products of sodium pentachlorophenoxide (Na-PCP) in an aqueous solution by sunlight, has been determined by chemical and spectroscopic evidences. Some of the chemistry and the absorption spectra of IV and its related compounds containing 3-cyclohexene-1,2-dione and spiroketal structures are also described.     

Relationship between adult height and body weight and risk of carotid atherosclerosis assessed in terms of carotid intima-media thickness: The Nagasaki Islands study

Background

Previous studies have reported an inverse association between height and risk of cardiovascular disease. However, evidence is limited for the association between risk of atherosclerosis and height. Further, although the association between atherosclerosis and body mass index (BMI) is reportedly positive, there have been no reports of studies on associations between height and atherosclerosis in relation to BMI.

Methods

We conducted a cross-sectional study of Japanese men aged 30 to 89 years undergoing general health check-ups.

Results

Of the 1,337 men, 312 were diagnosed with carotid atherosclerosis (carotid intima-media thickness (CIMT) ≥ 1.1 mm), but no significant association was found between height and carotid atherosclerosis for the entire study group. Stratification by BMI status of those analytical findings disclosed a significant inverse association between height and carotid atherosclerosis among overweight (BMI ≥ 25 kg/m²) but not among non-overweight (BMI < 25 kg/m²) men. The classical cardiovascular risk factors-adjusted odds ratio (OR) and 95% confidence interval (CI) of carotid atherosclerosis for an increment of one SD (standard deviation) in height (6.70 cm) were 0.71 (0.54 to 0.94) for overweight (BMI ≥ 25 kg/m²) and 1.05 (0.87 to 1.27) for non-overweight (BMI < 25 kg/m²) men.

Conclusion

Independent from classical cardiovascular risk factors, height was found to be inversely associated with carotid atherosclerosis for overweight but not for non-overweight men.     

Bifidobacteria Abundance-Featured Gut Microbiota Compositional Change in Patients with Behcet’s Disease

Gut microbiota compositional alteration may have an association with immune dysfunction in patients with Behcet’s disease (BD). We conducted a fecal metagenomic analysis of BD patients. We analyzed fecal microbiota obtained from 12 patients with BD and 12 normal individuals by sequencing of 16S ribosomal RNA gene. We compared the relative abundance of bacterial taxa. Direct comparison of the relative abundance of bacterial taxa demonstrated that the genera Bifidobacterium and Eggerthella increased significantly and the genera Megamonas and Prevotella decreased significantly in BD patients compared with normal individuals. A linear discriminant analysis of bacterial taxa showed that the phylum Actinobacteria, including Bifidobacterium, and the family Lactobacillaceae exhibited larger positive effect sizes than other bacteria in patients with BD. The phylum Firmicutes and the class Clostridia had large effect sizes in normal individuals. There was no significant difference in annotated species numbers (as numbers of operational taxonomic unit; OTU) and bacterial diversity of each sample (alpha diversity) between BD patients and normal individuals. We next assigned each sample to a position using three axes by principal coordinates analysis of the OTU table. The two groups had a significant distance as beta diversity in the 3-axis space. Fecal sIgA concentrations increased significantly in BD patients but did not correlate with any bacterial taxonomic abundance. These data suggest that the compositional changes of gut microbes may be one type of dysbiosis (unfavorable microbiota alteration) in patients with BD. The dysbiosis may have an association with the pathophysiology of BD.     

Structural Basis for the Dual Substrate Specificity of DOCK7 Guanine Nucleotide Exchange Factor

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Generation of cell lines with tetracycline-regulated autophagy and a role for autophagy in controlling cell size

Autophagy is an intracellular bulk degradation system. We established mouse fibroblast lines coupling the Tet-off system with an Atg5-/- mouse embryonic fibroblast line to artificially regulate autophagic ability. In the presence of doxycycline (Dox), Atg5 expression was completely suppressed and these cells were autophagy-defective. After removal of Dox, autophagic ability was restored within 6 h. Very low levels of Atg5 could induce an autophagy competent state. We applied this novel system to examine the contribution of autophagy to controlling cell size. Cell size reduction in response to starvation was significantly inhibited in cells unable to undergo autophagy. The generated cell lines will be useful reagents for future mechanistic studies into the regulation and physiologic significance of autophagy.